by Operation Leader would have caused even greater damage to the German war effort than the shipping losses. This is in line with a wartime assessment by the British Ministry of Economic Warfare, which estimated that the raid was the main factor responsible for a 58 percent decrease in the amount of iron ore shipped from the important northern Norwegian port of Narvik during October 1943. Operation Leader was both the only offensive operation undertaken by the US Navy in northern European waters during World War II, and the last major American operation in this theatre of the war. Ranger remained with the Home Fleet until being replaced by British aircraft carriers in late November 1943, during which time she took part in a patrol of the Norwegian Sea. The carrier departed Scapa Flow on 26 November, and arrived in Boston on 6 December. Ranger was used to train aircrews and transport aircraft for the remainder of the war, with no further combat. The German forces in Norway were taken by surprise during Operation Leader. The area had not been raided by carrier-borne aircraft for two years, and preparations for such an attack were inadequate. Precautions against further raids were put in place, and the British carrier forces which repeatedly attacked Norway until the end of the war did not encounter any concentrations of shipping like that located by Rangers airmen off Bodø. Operation Leader revealed a serious weakness in the composition of the German armed forces in occupied Norway, which were lacking sufficient numbers of combat aircraft to respond effectively to Allied attacks. Following the attack, the Germans searched the area for radio transmitters, arresting several local Norwegians and narrowly missing the agents of the "Pisces" group. The two members of the "Pisces" team were evacuated to the United Kingdom by Consolidated PBY Catalina flying boat on 24 November 1943. The last SIS agents of the "Crux" group were evacuated from Renga by a No. 330 Squadron RAF Catalina on 6 June 1944, but the transmitter on the island continued sending reports to the United Kingdom for the duration of the war, manned by a local volunteer who had been trained by the agents. The wreck of the Avenger torpedo bomber shot down in the operation was located off Fagervika with the help of local Norwegians in 1987, and partially salvaged by the Royal Norwegian Navy. The remains of